| Used some typical low-P tolerant rice genotypes which were screened in seedlingstage and identified in full-life stage, in contrast with neutral soil, this research screenedin acid soil and alkali soil, Thus, some inbreds of low-P resistance and low-P sensitivewere obtained under three pH values. Meanwhile, some typical lines were selected tostudy their nutritional characters and physiological mechanism for low-P tolerance. Themain results of this study were summarized as follows:1.Though seedling screening with soil culture in contrast with neutral soil, to gainsome typical low-P tolerant rice genotypes under three pH values.2.The treatment of low phosphorus towards different rice breed caused someinfluence on their biology traits. When the phosphorus level keep in 35mg/kg, thenumber of tiller, valid spike and output of single plant had some decrease comparing withthe regular level.3.The biology traits have evident differences on soil types and rice genotypes. Therelative tiller ratio were lowest in acid soil at tiller and booting stages, the order of therelative biology mass on different stages was alkali soil＞acid soil＞neutral soil. Theinfluence of treatment of low phosphorus towards different rice breed in alkali soil wasless than the other soils, it was incarnated in the grain set rate, single plant yield,available spike and the number of small spike. It was dissimilar that the influence ofphosphorus on rice under different pH value soils at different stage. The influence of lowphosphorus on E.Wan 13 was the least in alkali soil and neutral soil at tiller stage; Theinfluence of low phosphorus on 850, 1574 and 1079 was the least in alkali soil at bootingstage; At mature stage in the three pH value soils, the 1000-kernal weight and singleplant yield of 1574 were the most, the order of the grain set rate was the routine rice＞thehybrid rice＞the low-P tolerance genotype＞the low-P sensitivity genotype, the availablespike and the number of small spike of 1079 were the most, the low-P tolerant ability ofE.Wan 13 was feeble than the other breed, because it was the lowest of the relative singleplant yield of E.Wan 13.4.When the phosphorus level keep in 35mg/kg, The phosphorus absorption quantityand utilization efficiency of all genotype were different. It was the maximum of thephosphorus absorption efficiency of 850, 1574 and 1079 at tiller stage, the results showed that the low-P tolerance genotype had stronger phosphorus absorption ability; itwas the maximum of the phosphorus absorption and utilization efficiency of the threelow-P tolerance genotypes at booting stage; When the mature stage was coming, therelative phosphorus absorption of 1079 and 1574 achieved 59% and 65%. As for as thetransport and distribute amount of phosphorus from the body to the grain of the plant, thebreed of 850, 1574 and 1079 were lower than the other breeds, so the rice that endure thelow phosphorus are better than the other rice cultivars in the aspect of saving the sourceof phosphorus. When the phosphorus level keep in 35mg/kg, the absorption of K, Ca andMg of all rice cultivar had some decrease comparing with the regular level's, but thepercentage composition of Ca and Mg were increased.5.The absorption and utilization of phosphorus and other nutrirent elements haveevident differences on soil types and rice genotypes. At tiller stage it was the highest ofthe absorption and utilization ability of phosphorus in alkali soil. The absorption ofphosphorus of 850, 1574, 1079 and Shan You 63 is higher then 99012 and E.Wan 13; Theabsorption of phosphorus in alkali soil was higher then the other soil types, while relativephosphorus utilization efficiency just ran the other way round. The absorption ofphosphorus of 850 and 1574 was highest; The phosphorus utilization efficiency at maturestage was higher then booting stage. The absorption of K,Ca and Mg of tiller stage waslowest, and it was similar between booting and mature stage. The order of the content ofK and Ca was tiller stage＞booting stage＞mature stage, when the content of Mg ofmature was lowest, and it was similar between booting and mature stage. At tiller stagethe content of K in neutral soil was the lowest, and the same as the content of Mg in acidsoil, the absorption of K and Mg in neutral soil was highest. It was higher of the contentof Ca of the three low-P tolerance genotypes in alkali soil then the other dee cultivars, atthe same time, in three pH value soils the absorption of Ca was higher then 99012 andE.Wan 13, and the relative content of K was highest. The Mg-absorbed capacity andrelative Mg-absorbed capacity of the various genotypes within booting stage were neutralsoil＞alkaline soil＞acid soil; in mature stage, the tendency of Mg-absorbed capacity ofsignal plant was neutral soil＞alkaline soil＞acid soil, the relative content of Mg wasalkaline soil＞neutral soil＞acid soil. The content of Ca were alkaline soil＞acid soil＞neutral soil.6.It was found that, under P-low tolerance condition, the ratio of N, P, K, Ca and Mgabsorbed by 5 genotypes of rice were deduced, and that of Zn was raised, but P-lowtolerance genotypes rice still had higher absorbing capacity of N, P, K, Mg and Zn.7.The rice cultivars for different genotypes selected in this study all representeddefinitive activated absorbing capacity to indissoluble Fe-P, Ca-P and Al-P in P-low menace condition, and then, Fe-P was activated more easily. But different rice cultivarshas genotype variance on absorption and utilization for indissoluble P. P-low tolerancerice cultivars such as 943 had maximum quantity of Ga-P and Al-P, and the absorbingcapacity of 943 under CK treatment condition was higher than that of other 4 genotypes(except 99056), this illustrated that the rice cultivars 943 not only has strongly absorbingcapacity of P, but also was more suitable for P-absorption in P-low condition. But thesensitive genotype rice cultivars such as 99012 had better P-absorption capacity on Ptreatment conditions, even the P-absorption capacity exceeded that of P-low tolerancerice cultivars such as 99011 and 943, but the other 4 treatments such as Fe-P, Ca-P, Al-Pand normal P had low P-absorption, the conclusion was got that 99012 absorbs lowdensity P uneasily.8.From 43 families of rice mutant materials that acquired by primary selection, therewere 13 genealogies of rice mutant materials measured up to standard had been obtainedrepeatedly, and there were 8 co-separation families that detected with PCR appearedpositive reaction. 8 co-separation families were transported and harvested in matureseason, The stability will be detected through repeating selection in field latterly.
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